Fluid pressure device



Sept. 16, 1941.

FLUID PRESSURE DEVICE c. M. KENDRICK 2,255,784

Filed May 24, 1940 r k 6 Sheets-Sheet 2 INVENTOR ATTORNEY p c. M.KENDRICK 2,255,784

FLUID PRESSURE DEVICE Filed May 24, 1940 6 Sheets-Sheet 3 INVENTORATTORNEYS P 4 c. M. KENDRICK 2,255,784

FLUID PRES SURE DEVICE Filed May 24, 1940 6 Sheets-Sheet 5 INVENTOR MMMUIWYZ ATTORNEYS Sept. 16, 1941. c. M.-KENDRICK FLUID PRESSURE DEVIGI:

Filed May 24, 1940 s Sheets-Sheet INVENTOR W W Z QM Patented Sept. 16,1941 UNITED STATES PATENT OFFICE FLUID PRESSURE DEVICE Charles M.Kendrick, New York, N. r., assignor to Manly Corporation, Washington, D.0., a corporation of Delaware Application May 24, 1940, Serial No.336,956

23 Claims.

valve mechanism and systems therefor and particularly to vane typemotors and controls therefor, although certain features of the inventionare applicable to pumps of the vane type.

Vane type motors of this general class include a vane track thatsurrounds the rotor and vane assembly and is adapted to contact theradially outer ends of the vanes and to guide and control their inwardand outward motion as the rotor revolves. For quiet and satisfactoryoperation of the motor it is practically essential that the outer endsof the vanes be urged into contact with the vane track when operation ofthe motor is started and that such contact be maintained continuouslyduring its operation. In order to provide this track-contacting andtrack-following action of the vanes it is necessary to supplement theaction of centrifugal force with an auxiliary force acting to urge thevanes outward, at least during the portion of their rotary travel inwhich they are passing through the intake area or areas of the motor, sothat the outer ends of the vanes will be held firmly in contact with thesurrounding vane track and thus provide a movable resistance to thepressure fluid admitted to the outer ends of the vanes, whereby rotarymotion is imparted to the rotor and driven shaft of the vane motor. Inthe vane motor of the present invention, fluid pressure means areutilized to provide this' auxiliary force and this is accomplished byintroducing or admitting, behind the inner ends of the vanes, pressurefluid having a pressure greater'than but related to the pressure of thefluid admitted to the pressure area or areas atthe outer ends of saidvanes, as fully explained in my co-pending application flled March 28,1938, Serial Number 198,449. Thus fluid under two different but relatedoperating pressures is used; the fluid having the higher of these twopressures, which for convenience is termed the difierential highpressure fluid, is admitted to the radially inner ends 01 the vaneswhile fluid under the lesser of these two pressures (for conveniencetermed the operating pressure fluid) is admitted to the pressure areasat the radially outer ends of the vanes oi the vane motor. Thediflerential high pressure fluid and the operating pressure fluid forthe vane motor may be provided in any preferred manner and the means bywhich they are supplied forms no part per se of the present invention.For purposes of illustration, however, the embodishow means by whichthese two difierent but related pressures are obtained by passing thesupply of fluid going to the motor through "differential pressure orresistance valve mechanism positioned in the fluid supply conduit, aswill be later more fully explained; but it is to be understood that anyother suitable means may be employed for providing these two differentbut related pressures such, for example, as other means disclosed inco-pending application Serial Number 198,449 or in co-pendingapplication flied May 5, 1939, Serial Number 271,874.

Co-pending application Serial Number 198,449 discloses an arrangementfor a reversible vane type fluid motor in which the difierential highpressure fluid is continuously supplied to the radially inner ends ofall the vanes. With this arrangement the vanes are urged radiallyoutward while passing through the intake or high pressure areas of themotor by an auxiliary force produced by the difference in pressuresexisting between the differential high pressure fluid and the operatingpressure fluid and in practice this difference in pressures isrelatively small such as -75 lbs. per sq. in. But while passing throughthe outlet areas of the motor, during which time the vanes are movingradially inward, the vanes are urged radially outward by aiorce producedby substantially the full or absolutepressure value of the differentialhigh pressure fluid as the fluid in the outlet areas which acts on theexposed radially outer ends of the vanes therein is usually under littleor no pressure. While this arrangement has been found to functionsatisfactorily as regards smoothness and quietness of operation, itnevertheless provides unneeded radially outward auxiliary force on thevanes as they pass through the outlet areas and this force, which isusually high and frequently as much as that produced by a fluid pressureof 1000 lbs. per sq. in. on the inner ends of the vanes, causes wear ofthe vanes and vane track, unnecessarily increases the triotion betweenthese parts and thus reduces the efllciency of the motor.

One object of the present invention is to provide an improved reversiblevane type rotary motor, together with associated controlvalve mechanismand system therefor, of increased efliciency and free from theobjections just above mentioned.

Another object is to provide an improved reversible vane type motor andassociated control valve mechanism and system therefor in which mentsillustrated in the accompanying drawings the differential high pressurefluid is supplied 3 fluid in said outlet areas so that the hydraulicforces acting radially on said vanes are substantially balanced as thevanes pass through the outlet areas. 7

A further object is to provide a motor of this character, together withassociated control valve mechanism and system therefor, in which theforegoing operating conditions are provided, ir-

respective of the direction of rotation of the rotor, and in which thefluid connections necessary to provide these operating conditions areestablished upon change in direction of the rotors rotation.

Another object of the invention is a novel and improved means forholding the vanes in contact with the track during any overrun of themotor upon reversal; and particularly a means by which saidcontact ismaintained by a relatively small force.

- Other objects will appear from the description whichfollows.

The widest present use for vane motors this general class is ashydraulic devices, that is to say, devices for handling, or whose motivefluid is a liquid, such for example, as oil. The present invention willaccordingly be described in connection with such use although it will beunderstood that certain features of the invention are also applicable todevices operating with elastic fluids. It will further be understoodthat the invention is applicable equally to vane type motors of thisgeneral class in which the dis- 1 placement or fluid capacity perrevolution of the rotor 'is constant (termed a constant capacity motor)and to such motors in which the displacement or fluid capacity perrevolution of the rotor is variable (termed a"variable capacity motor).

The invention will be understood from a consideration of theaccompanying drawings which illustrate, by way of example, severalembodiments of the present invention in and in connec- 1 lustrativeembodiment of a reversible vane. motor constructed according to thepresent inven- 1 tion;

Fig. 2 is a fragmentary longitudinal sectional view taken along thelines 2-2 of Figs. 3 and 4, showing certain parts of the fluid circuitand the 1 method of mounting the shaft;

Fig. 3 is a view in vertical section transverse the axis of rotation andtaken along the lines 3-3 of Figs. 1 and 2;

Fig. 4 is also a view in vertical transverse section but is taken alongthe lines 4| of Fig. 1 r and looking in a direction Fig. 3;

opposite to that of Fig. 5 is an outer or end elevation of the cover 1or end head member with certain of the fluid passages therein shown indotted lines;

Figs. 5a, 5b and 5c are sectional views through the end head, showingcertain of the fluid passages in section, and taken along the lines5a-5a, ib-Sb and 50-50 respectively of Fig. 5;

Fig. 6 shows an inner elevation of one of the the end head and is takenalong the line members of the vane motor, for convenience termed an endplate or cheek plate;

Fig. '7 is a sectional view through the control .valve mechanism whichcontrols the flow and distribution of fluid through the several passagesin of Fig. 1;

Fig. 8 is a diagrammatic view, partly in section, of a fluid systemincluding the vane-type motor illustrated in Figs. 1 to '7 inclusive,with certain minor modifications to be later pointed out; and

Figs. 9 and 10 are also diagrammatic views, partly in section, showingmodifications.

Referring now to Figs. 1 to 7 inclusive, the motor includes a casing I 0formed with an openended cavity for the rotor 15 and associated parts asshown in Figs. 1, 2 and 3. The rotor cavity is closed (Figs. 1 and 2) byan end head or cover member H which is attached to the casing 10 as bycap screws l2. The rotor I 5 is provided with a plurality of vanes I!which are movable in a substantially radial direction inward and outwardin the vane slots 16 (Figs. 1, 2 and 3). A vane track ring 25 surroundsthe rotor and vane assembly and its inner circumferential surface 26(Fig. 3) forms a track adapted to contact the radially outer ends of thevanes H as the rotor revolves and to guide and control the vanes intheir inward and outward movement; the surface 25 will hereinafter bereferred to as the vane trac The rotor l5 and driven shaft 20 may bemounted and the two parts may be operatively connected with each otherin any appropriate manner. Inthe present instance the rotor I5,

' shaft 20, their mountings and the operative connections therebetweenare the same as disclosed in my co-pending application filed December 8,1939, Serial Number 307,755. As shown in Fig. 2, the shaft 20 isrevolubly supported by a pair of bearing elements 23 and 24 carried bythe casing l0 and the rotor I5 is mounted on the end of the shaft 20which projects intothe rotor cavity. For this purpose the end of theshaft 20 is formed with axially extending splines 2| (Figs. 1, 2 and 3)and the rotor I5 is formed in its central opening with mating splines l8(Fig. 3). The arrangement is such that the rotor I5 is freely movable inan axial direction on the shaft splines 2| while permitting a limitedangular or rocking motion of the rotor l5 relative to the shaft 20 insuch manner that the cheek plates 34 and 35, to be presently described,determine the axial and angular position of the rotor on the shaft andthe plane of rotation of the rotor as changeable upon reversal as willbe more fully explained presently. As shown in Fig. 3, the difullyexplained in co-pending application Serial Number 307,755 abovementioned. v

-The rotor I5 is hydraulically balanced with respect to all forcesimposed thereon by fluid pressure. Hydraulic balance of forces acting onthe rotor in a radial direction is obtained by dividing the spaceintermediate the periphery of the rotor l5 and the vane track 25 intotwo equal and oppositely positioned fluid sections, each fluid sectioncomprising a working chamber flanked by an inletarea andan outlet area,the inlet area and outlet area of each section being intervision betweenthe two fluid sections is effected by cooperation of the rotor l5 andthe outer ends of the vanes I! with the vane track 26 at the reons ofthe vane tracks least diameter which in the present embodiment isadjacent the horizontal centerline. The vane track 26 is preferablyprovided at each of these points of division with an are 21, forconvenience termed the sealthe outlet ports, depending upon thedirection of flow of fluid in the circuit. The ports 36 and 31 of thecasing cheek plate 34 are also partially with the rotor l5 and termedthe working arcs,

which are located in the regions of greatest diameter of the vane track26. Each working chamber extends in a circumferential direction for anarcuate distance substantially equal to the distance between the outerends of two adjacent vanes I! which at any given instant are moving incontact with the corresponding working arc 3|. Operating pressure fluidis admitted between the vanesas they move through the inlet areas towardthe working chambers and fluid is discharged as the vanes recedetherefrom through the areas which at the time are the outlet areas ofthe two fluid sections. section which at any time is the inlet area isthus at all times separated from the area which is then the outlet areaof that fluid section by at least one of the vanes l1, and this is thecase regardless of which area is the inlet area and regardless ofdirection of rotation of the rotor; the difference in pressures on theopposite sides or faces of such vanes causes rotation of the rotor l5.The portions of the vane track 26 intermediate the sealing arcs 21 andworking arcs 3| may be given any suitable curvature producingsatisfactory rates of inward and outward movemen of the vanes H as therotor l5 revolves.

The area of each fluid" shown in Fig. 3 and the ports 31 are also shownin the sectional view of Fig. 2. Operating pressure fluid is admitted tothe outer ends of the vanes through either the pair of ports 36 or thepair of ports 31, depending upon the direction of the flow of fluid inthe circuit, inthe casing cheek plate 34, and similarly, fluiddischarged or exhausted by the outer ends of said vanes passes outthrough the other pair of ports of the same cheek plate. The ports 36and 31 of the end head cheek plate 35 function principally as balanceports to contain fluid under the same pressure as that in thecorresponding ports of the casing cheek plate 34 in order to producehydraulic balance of the rotating parts, as already The sides or axialends of the working chambets are closed by a pair of mating disc-shapedmembers 34 and 35 (Figs. 1, 2, 3 and 6), for convenience termed endplates or "cheek plates, which are provided with holes at their centersfor the shaft 20. The outer surfaces of the cheek plates 34 and 35 fitsnugly against the wall surfaces of the casing l0 and end head I lrespectively and form "substantially fluid tight fits with the severalports and passages to be presently described. The inner or opposingfaces of the cheek plates and 35 form fluid tight fits with the sides ofthe vane track ring 25 by which they are axially positioned with respectto the rotor 15 in such manner that the rotor is permitted to turnfreely while its sides and the sides of the vanes l'l form substantiallyfluid tight running fits with the adjacent faces of the cheek plates 34and 35. The cheek plate 34 will hereinafter be termed the casing cheekplate and the cheek plate 35 wil be termed'the "end head cheek plate.

The check plates 34 and 35 are provided with co-extensive mating ports(Figs. 2, 3 and-6) the ports of one cheek plate being axially oppositethe ports of the other cheek plate when the parts are in position in thecasing I!) so that all forces exerted upon the rotor l5 and vanes l1 inan axial direction by fluid pressure are thus completely balanced.Theports in the cheek plates 34 and 35 will be best understood from Fig.6 which shows an inner elevation or the rotor face of the end head cheekplate 35. Referring to Fig. 6, each cheek plate is provided with a pairof diametrically opposed arcuate slots or ports 36 and a similar pair ofdiametrically opposed slots or ports 31; either pair of these ports maybe the inlet ports and the other pair will then be stated.

The portion of the fluid circuit for conveying fluid to and from theouter ends of the vanes H also includes a pair'of branched channels 40and 4| respectively (Figs. 2 and 4) which are formed in the casing andwhich are similar to the fluid channels shown in application SerialNumber 307,755. The fluid channel 4| is connected with the fluid conduit43 and with the ports 31- of the casing cheek plate 34 by slantedpassages 44 (Fig. 2). The fluid channel 40 is similarly connected withthe fluid conduit 42 and is also connected with the two ports 36 of thecasing cheek plate 34 as by slanted passages not shown for conveniencebut similar to the slanted passage 44 shown in Fig. 2.

With the arrangement hereinbefore described operating pressure fluid'admitted to the conduit 42 will pass into the ports 36 of the casingcheek plate 34 and the fluid areas connected with said ports 36 willthen be the intake areas; operating pressure fluid acting on theadjacent faces of the vanes I! that are then in contact with the workingarcs 31 will cause rotation of the rotor I5 and shaft, 20 in a clockwisedirection as viewed in Fig. 3; the fluid areas connected with the ports31 of the casing cheek plate 34 will then be the outlet or dischargeareas and the-fluid discharged by the outer ends of the vanes will passout through the portsv 31 of said cheek plate 34, through the connectingpassages 44 and channel 4| and out through the conduit 43. Similarly,operating pressure fluid admitted to the conduit 43 will pass to theports 31 of the casing cheek plate 34, causing rotation of the rotor l5and shaft 20 in a counter-clockwise direction as viewed in Fig. 3, andfluid exhausted by the outer ends of the vanes I! will pass out throughthe ports 36 of the casing cheek plate 34, through the slanted passages44, the channel 46 and finally out through the conduit 42.

Satisfactory operation of the motor requires ends thereof during thetime that said outer ends are passing through whichever area of eachfluid section is at the time its outlet or discharge area. The means bywhich these operating conditions are provided, irrespective of directionof For increased efrotation of the rotor 15, and by which they arechanged to correspond to change in location of the intake and outletareas upon reversal of direction of rotation of the rotor l5 areimportant features of the present invention and will now be describedand explained. o

Referring now to Fig. 6, each of'the cheek plates 34 and 35 is providedwith four pairs of mating arcuate ports 46, 41, 48 and 49 respectivelyin the facesthereof adjacent the rotor l5- These ports (for .conveniencehereinafter termed the vane slot ports) are positioned to registersuccessively with the inner ends of the vane slots l6 as the rotorrevolves. and the vane slot ports of each pair are positioneddiametrically opposite each other. All fluid passing to andfrom theinner ends of the vanes and vane slots passes through the vane slotports-of the end head cheek plate 35 and hence all of the vane slotports in said check plate 35 extend through its entire thickness; thevane slot ports of the casing cheek plate 34 ;serve principally asbalance ports receiving :thirsupply of fluid through the vane slots l6an hence they are merely recessed in the rotor faceo that check plate asshown in Figs. 1 and 2.]

Each fot .the pair of vane slot ports 46 is adapted to connect with theinner end of each vane slot l6 during the time that the outer end of thevane therein is passing through the fluid area con'n'ected'withthecorresponding radially Y outward port 36; and similarly, each of thepair of vane slot ports 41 is adapted to connect with i the inner end ofeach vane slot it during the time that the outer endlof the vane thereinis'passing throughthe fluid area connected with the cor- I responding Iradially outward port 31. In the 1 same manner, each of the pair of vaneslot ports 48 and each of the pair of. vane slot ports 43 is 1 adaptedto' connect with the inner end 1 of each 1 .vane slot during the timethat the outer end of the vane therein i's traversing the correspondingsealing arcll or working arc 3|.

The end heacl II is provided with appropriate fluid passages forconveying fluid to and from v each pair of thevane slot ports 46, 41, 48and 48 of the end head. cheek plate 35,'as shown in Figs.

1, 5, 5a, 5b, and 5c. The two pairs of vane slot 3 ports 48 and .49 areat ,all times supplied with difj ferential high pressure fluid,irrespective of the direction of flow of fluid tothe outer ends of thevanes and irrespective ofsthe directionof rotation of the rotor; eachof.said vane slot ports 48 and V4!! in the end head'cheek plate 35accordingly registers with one end of its corresponding slanted radialpassage 58. The four cheek plate 35 registers with an arcuate port 55(Figs. 5 and 5a) in the adjacent or inner wall of the end head I l andsaid ports 55 in turn connect with a cored passage 56 connecting withthe inner end of an axial hole or passage 51 which leads to the outerface of the end head H. The general shape and arrangement of the twocored passages 53 and .56 may be observed in the dotted lines of Fig. 5and from the sectional views of Figs. 5a, 5b and5c, in which it will benoted that said passages 53 and 56 are positioned in different planes inthe end head II and that each of them surrounds a solid por-. tionadjacent the vertical and horizontal centerlinesof the end head, inwhich solid portion the axial hole or passage 5| is drilled.

With the above described arrangement it will be seen that all fluidgoing to or from the inner ends of the vanes l1fpasses through the holes0r passages 5|, 54 and 51 that lead through to the outer face of the endhead II. The flow of fluid through these holes or passages is regulatedby valve mechanism which will now be described.

The valve mechanism employed to control the flow of fluid to and fromtheinner ends of the vanes l1 through the vane slot ports 46, 41, 48 and43 of. the cheek plate 35 is shown in the sectional view of Fig. 7and'is contained in a housing 68. Thehousing 60 is attached to the outerface of the end head II as shown in Fig. 1 by cap screws or he like, notshown, in such manner that there is a fluid tight joint at the point ofconnection of each of the several passages therein that connect withpassages in said end head ll. Differential high pressure fluid, obtainedfrom any preferred source in any preferred manner, is admitted to thehousing 68 through a conduit 45 which connects with a slanted passage 6|leading to an oppositely slanted passage 62 as shown in Fig. 1. Theslanted passage 62 'extends to the face of the housing adjacent the 7end head II where it connects with the axial hole 1 or passage 5|, sothat differential high pressure fluid is at all times supplied to thetwo pairs of vane slot ports 48 and 43.

The other end of the passage 62 leads to and connects with an annularport 64 in the valve bore 63 (Figs. 1 and 7) positioned intermediate theannular ports 65 and 66. The annular port 65 connects with a passage 61,as shown by e dotted lines of Fig. 7, which leads to the face 'of thehousing. 68 adjacent the end head I I and the outer 'end of said passage61 is adapted to conpassages 58 converge toward and connect with anaxial hole or passage 5| which extends to the outer face of the end headll (Fig. 5c) The ar.. T rangement may be observed from the dotted linesof Fig. 5 and also fromthe sectional-view of Fig.

1 50 which shows the two passages58 leading to the pair of vane slotports 48. and in the sectional view of Fig.1 which shows the twopassages 58 that connect with thevane slot ports 49.

Each of the pair of vane slot ports 46 of the of the end head I I. In asimilar manner, each of the pair of vane slot ports 41 of the end headnect with the axial passage 54 in said end head II. The annular port 66is similarly connected with apassage 68 (dotted lines in Fig. 7) leadingto and connecting with the axial passage 51 in the end head II. Theactual points of connection of the passage 61 with the passage 54 and ofthe passage 68 with the passage 51 are not shown but will be understoodfrom the description and from the parts as illustrated in the drawings.

Slidably fitted within the valve bore 63 is a valve piston 18 (Figs. 1and 7) formed with three spaced heads 1|, 12 and 13 respectively. Move--ment of the valve piston in the valve bore is limited by reduced endportions 14 extending from the heads H and 13, each of which reducedportions 14 is adapted to enter the recess 15 in its corresponding endcover 16 that closes that end ofsaid valve bore, the recesses 15 servingas dash-v pots to prevent sudden and violent striking of the end of thevalvepiston against the end covers.

The enlarged end portions 11 and 18 (Fig. 7)

of the valve bore are connected with the ports 36 and 31 respectively inthe end head cheek plate 35. For this purpose the end portions 11 and 18connect with the inner ends of a pair of passages 19 and 80 (dottedlines of Fig. '7) which are adapted to connect with a corresponding pairof axial passages 8| and 82 extending through the end head H (Figs. 5,5a and 5b) and leading to one of the ports 36 and one of the ports 31respectively in the end head cheek plate 35; the passage 82 is alsoshown in the sectional view of Fig. 1. The opposite ends of the valvebore are thus at all times supplied with fluid under the same pressuresas existing in the ports 36 and 31 respectively and the difierence inthese pressures acts on the valve piston 16 and determines its locationin one or the other of its extreme positions in the valve bore; thisdifference in pressures also acts to move the valve piston"!!! from oneextreme position to the other responsively to change in direction offluid flow in the conduits and passages leading to the outer ends of thevanes, this change being incident to reversal of the rotor. In otherwords, the valve piston 16 occupies its extreme position toward theright in which it is shown in Fig. '7 when the ports 31 are the intakeor high pressure ports, the ports 36 then being the outlet orlow'pressure ports, but said 'valve piston 10 is shifted instantly toits extreme position toward the left upon reversal and when the ports 36become the intake or high pressure ports.

The heads 1!, 12 and 13 of the valve piston 10 are so positioned andarranged that they establish proper fluid connections with the vane slotports 46 nad 41 to provide the desired operating conditions, ashereinbefore set forth, when said valve piston 16 is in one or the otherof its extreme positions, these connections corresponding with therequirements of the vanes for proper operation. For example, as alreadystated the valve piston 10 is moved to and occupies its extreme positiontoward the right when the ports 31 are the intake or high pressureports. In this extreme position, the reduced portion of the valve piston10 intermediate the heads 12 and 13 establishes fluid connection betweenthe ports 66 and 64 and at-the same time said heads 12 and 13 cut ofifluid communication between these ports and all other portions of thevalve bore. Differential high pressure fluid then passes from the port64 into the port 66, through the intervening passages and into the vaneslot ports 41 so that the vanes l1 are urged into contact with the vanetrack during the time they are'passing through the fluid area of eachfluid section that is connected with its port 31. At the same time thehead 1| has moved into the enlarged end portion 11 of the valve bore andfluid is than free to pass out from the vane slot ports 46, through theintervening passages and the port 65, into the valve bore 63 and out ofthe enlarged end portion 11 of said valve bore through the passages 19and BI and finally into the connected port 36 in the end head cheekplate 35. Fluid discharged by the inner ends of the vanes l1 through thevane slot ports 46 thus joins with the fluid being discharged by theouter ends of the vanes I1 and passes away through the fluid channel 40and conduit 42. As already stated, the ports 36 are the outlet portswhen the valve piston 10 is in its extreme position toward the right,and it will thus be seen that the fluid pressure in the vane slot ports46 is substantially the same as that in the ports 36 so that there issubstantially no fluid imposed force active to urge the vanes intocontact with the vane track during this portion of their rotary travel,in which said vanes are moving radially inward; friction and wear arethus reduced and efiiciency increased. 1

Upon reversal of direction of fluid flow in th fluid passing to theouter ends of the vanes, the ports 36 will become the intake or highpressure ports, the ports 31 will become the low pressure or outletports and thedirection of rotation of the rotor will be reversed.Instantly upon such reversal of fluid flow, the valve piston 10 will bemoved to its extreme position toward the left and the above-describedconnections of the vane slot ports 46 and 41 will be reversed. Thus, theport 65 will be connected with the port 64 and dif-.

ferential high pressure fluid will be supplied to the vane slot ports46. Fluid discharged by the inner ends of the vanes through the vaneslot ports 41 will then pass through the intervening connections and theport 66, into the left hand end 18 of the valve bore 63, through thepassages and 62 and into the connected port 31 of the end head cheekplate 35.

It is thus seen that, by the arrangement here provided, differentialhigh pressure fluid is at all times supplied to the inner ends of thevanes during the time that the. outer ends thereof are traversing theworking arcs 3| and sealing. arcs 21. It will further be seen thatdifferential high pressure fluid is also supplied to the inner ends ofthe vanes during the time they are passing through whichever area ofeach fluid section is at the time its intake or high pressure area andthat the inner ends of the vanes are connected with the exhaust whilethe outer ends thereof are passing through the other areas which arethen the outlet areas. It will also be seen that these connections areprovided regardless of the direction of rotation of the rotor l5 and areinstantly changed upon reversal. It will also be observed that thesechanges take place responsive to relative pressures existing in theports 36 and 31 and that the passages 19, 80, 8! and 62 connecting saidports 36 and 31 with the ends of the valve bore serve the double purposeof supplying pressure fluid to act on the valve piston to control itsposition and movement and also provide a path of flow for fluiddischarged by the inner ends of the vanes H.

The fluid circuit described and explained in connection with Figs. 1 to'1 inclusive is schematically shown in Fig. 8 which also shows adifferential pressure or resistance valve in the supply line forproviding the differential high pressure fluid and a reversing valve forreversing the direction of fluid flow to and from the motor in order toreverse the direction of rotation of the rotor I5. The same referencenumerals have been used to designate the portions of the fluid circuitshown in Fig. 8 that correspond to like numbered portions of the circuitdescribed in connection with Figs. 1-7. In Fig. 8 the valve mechanismfor controlling the flow of fluid to and from the inner ends of thevanes I1 is the same as that shown in Figs. 1 and '7 except for minormodifications such, for example, as the connections by which the supplyof differential high pressure fluid for the vane slot ports 48 and 49passes through the annular port or counterbore 64 of valve bore 63 inthe arrangement of Fig. 8 instead of passing directly from the com duit45 as in Fig. 1. It will also be notedv that the recesses or dash-potshave been omitted in the modified end covers 16' and that each of theenlarged end ports 11 and 18 of the valve bore has been provided with aspring 83 and a washer 84 which engages the adjacent head 1| or 13respectively of the valve piston 18 when said valve piston is displacedfrom its middle position toward the corresponding end or the valve bore.The inner ends 84' of the enlarged valve bore portions 11 and 18 serveas shoulders or stops that limit the inward movement of the washers 84and hence limit the distance through which the spring 83 in each end canexert a force upon the valve piston 18; with this arrangement, force isexerted upon the valve piston only by the spring in the end of the valvebore toward which it is displaced and the valve piston is returned toits center or middle position by the springs 83 whenever the samepressure exists in the ports 38 and 31.

In the fluid circuit illustrated in Fig. 8, pressure fluid for operationof the motor is delivered into the supply line 39 from any suitablesource, not shown, such, for example, as a pump, and a diflerentialpressure valve is positioned in said supply line intermediate saidsource and the reversing valve 98. The I difierential pressure valveshown in Fig. 8 is similar in principle to the corresponding mechanismdisclosed in copending application Serial Number 198,449 but differstherefrom in certain features of its construction. It includes a housing86 having .a valve bore suitably closed at both its ends and always incommunication with the reduced porp tion of said valve piston 88 thatseparates the two heads 89 and 98. The end of the valve piston 88adjacent the head 98 is adapted to be acted upon at all times by fluidhaving the same pres- I Two oppositely acting forces are thus broughtprovided with an annular inlet port 86 and an to bear on the valvepiston 88 and said piston, is moved until these opposing forces arebalanced. This balance of forces is effected by movement of the valvepiston 88 until the head 89 partially closes the discharge port 81,thereby increasing the resistance to flow therethrough and producing apressure in the inlet port 86 that exceeds the pressure existing in thedischarge port 81, so that the force exerted by the action of pressurefluid from the inlet port 86 upon the end of the valve piston adjacentthe head 98 equals the combined forces exerted by the action of pressurefluid from the discharge port 81 on the opposite end of the valve pistonand the supplementary force exerted thereon by the spring 96. The valvepiston 88 is thus moved to maintain the'fluid in the inlet port 86 at apressure exceeding the pressure existing in the discharge port 81 byanamount corresponding to the force exerted by the spring 96 at all timeswhen fluid passes through the discharge port 81. The spring 96 moves thevalve piston 88 to its fully closed position (in which no fluid can passfrom the inlet port 86 to the discharge port 81) whenever the pressuredifference is insuflicient to overcome the force exerted by said spring96, as when the motor is not being operated and no pressure exists inthe supply line 39; the valve piston 88 remains in its closed positionuntil suflicient pressure is built up to overcome the force exerted bythe spring, so that no pressure fluid can pass to the reversing valve 98etc. and to the outer ends of sure as that in the inlet port 86 and isaccordingly I connected with said port by a radial hole 9| thatconnectswith an axial hole 92 extending through the head 98. A smallshoulder 93 on the end cover 94 acts as a stop tor the valve piston andthus exposes substantially the full area of the end of the valve piston88 to the action ofthe pressure fluid when said piston is in its fullyclosed position. The end of the valve piston 88 adjacent the head 89 issimilarly adapted to be acted upon by fluid having the same pressure asthat in the discharge port 81 and the corresponding end of the valvebore is accordingly connected with the portion 39' of the supply line asby a passage 95 that enters the valve bore at a point that is notcovered or closed when the valve piston 88 is in its extreme openposition. The valve piston 88 is thus urged toward its fully openposition by action of pressure fluid from the inlet port 86 on the endof said valve piston adjacent the head 98 and this force is opposed bythe action of pressure fluid from the discharge port 81 upon theopposite end of said valve piston 88 and the supplementary force exertedby a spring 96, one end of which bears against the valve piston 88 andthe other end of which bears against the cover 91 that closes that endof the valve bore.

the vanes until the difierential high pressure has been established,thus assuring smooth starting of the motor, The pressure in the inletport 86 thus exceeds the pressure in the discharge port 81 whenever themotor is in operation, the diiference in pressures being a substantiallyconstant amount determined by the spring 96 and maintained irrespectiveof absolute pressures. Diflerential high pressure fluid for the innerends of the vanes is thus provided. The conduit The reversing valve 98schematically shown in Fig. 8 is provided with a bore having four ports99, I88, MI and I82 respectively and also having a rotatable body I83.The port 99 is connected with the portion 39' of the supply line and theport I82 is connected with the exhaust conduit 38 leading to thereservoir, not shown.

The ports I88 and IN are connected with the conduits 42 and 43respectively. With the body I83 in the position shown in Fig. 8, thesupply line 39 is connected with the conduit 43 and the conduit 42 isconnected with the exhaust conduit 38; operating pressure fluid thenpasses'to the ports 31 and the rotor revolves in a counterclockwisedirection as viewed in Fig. 3 as already stated; fluid is exhaustedthrough the ports 36 and passes out through the conduit 42. Rotation ofthe body I83 through connects the supply line 39' with the conduit 42and operating pressure fluid passes to the ports 36, causing the rotorto revolve in a clockwise direction: fluid is then exhausted through theports 31 and passes out through the conduit 43 which is then connectedwith the exhaust conduit 38. Upon such reversal of flow, the valvepiston 18 is moved to provide proper fluid connections for the innerends of the vanes, as already explained.

The method of and arrangement for supplying fluid to and dischargingfluid from the inner ends of the vanes as shown in Figs. 1 to 8inclusive, and explained in connection therewith, has been found to workwith entire satisfaction under ordinary conditions ofreversal in whichthe rotor I is substantially instantly stopped upon change of directionof fluid flow or in which said rotor I5 ceases to rotate in the intervalbetween the time that the supply of operating pressure fluid is cut offfrom one of the pairs of ports 36 or 31 and before the operatingpressure fluid is admitted to the other pair of these ports. Thisinterval may be extremely small and reversal may be made almostinstantaneously when the inertia load on the motor shaft 20 is small orsuch that rotation of the rotor I5 and its connected load may besubstantially instantly stopped by opposing action of the pressure fluid(within the limits of the maximum pressure to be employed in the system)on the outer ends of-the vanes upon reversal of fluid flow.

Large inertia loads require either an extremely high pressure toinstantly stop their rotation,

however, or a relatively longer time for decelera- I tion. In mostinstances it is not practical to instantly stop the rotation of largeinertia loads when rotating at high speeds because of the excessivelyhigh pressure required to effect such stoppage and it is customary todecelerate the load as rapidly as can be accomplished within certainreasonable pressure limits and during such deceleration the rotor tendsto over-run" and act as the rotor of a pump. The mechanism for supplyingfluid to and discharging fluid from the inner ends of the vanes, asshown in Figs. 1 to 8, does not operate to provide quiet andsatisfactory operation with certainty during such over-runythat is, withhigh inertia loads upon rapid reversal. The reason for this is that themotor tends to act as a pump during this period of deceleration, asalready stated, and since the valve piston 10 moves instantly uponreversal of relative pressures in the ports 36 and 31, no auxiliaryforce is available during over-run of the rotor to urge the vanes I1into contact with the vane track as they move outward through what arethen the low pressure (intake) areas and during the time that the speedof the rotor is constantly decreasing with corresponding decrease in thecentrifugal force available to move the vanes outward. The result isobjectionable noise, comparable to that encountered in any vane pump ifthe vanes do not move out properly during intake and in which the vanesare working against a substantial pressure such, for example, as 1000lbs. per sq. in. Figs. 9 and 0 illustrate modifications capable of quietand satisfactory operation under all operating conditions, includingvery rapid reversal under large inertia load. The arrangement of Figs. 1to 8 will be preferable where suited because of its greater simplicityand lower cost.- The arrangements of Figs. 9 and 10 are similar to thatof Fig. 8 except as relates to the mechanism having to do with the fluidsupplied to the inner ends of the vanes and the fluid dischargedthereby; all corresponding parts of Figs. 9 and 10 have been designatedwith the same reference numerals used to designate them in Fig. 8 andwill not be again described.

The valve piston I10 of Fig. 9 is provided with is generally similar tothe valve piston '18 of Fig. 7; the valve bore I63 is likewise similarto the valve bore 63 although the ports I64, I65 and I66 have beenenlarged to facilitate manufacture and to reduce the resistance to fluidflow therethrough. It willalso be observed that the port I64 is widerthan the head I12 of the valve piston and hence is not closed by saidhead I12 when the valve piston I16 is in and near its middle position sothat the ports I65 and I66 are bothconnected with the port I64 andreceive differential high pressure fluid when said valye piston is inand near said middle position. The pair of vane slot ports 46 isconnected with the port I65 and the pair of vane slot ports 41 issimilarly connected with the port I66 in a manner similar to that shownin Fig. 8.

The enlarged end portion I11 of the valve bore is provided with twofluid connections I8I and I82 respectively, here for convenience inillus tration shown as connectedwith the conduit 42 although they couldbe connected with port 36. The passage I8I connects with the adjacentend cover I16 and is .preferably restricted, as at I83, at its point ofconnection with the dash-pot recess I15. The passage I82 is providedintermediate its ends with a one-way spring-loaded check valve I84adapted to open to permit the passage of fluid from the enlarged endportion I11 of the valve bore to the conduit 42 but which closes toprevent the passage of fluid in the opposite direction. The valve boresenlarged end portion I18 similarly provided with two connections I85 andI86 respectively leading to and connecting with the conduit 43, thepassage I86 being provided with a one-way spring-loaded check valve I81.

The arrangement of Fig. 9 also includes an auxiliary pump I90, hereshown as a constant capacity pump, which takes its supply of fluid froma suitable reservoir, not shown, through an inlet passage I9I anddischarges its pressure fluid into the discharge passage I92. Thedischarge passage I92 has two branches I93 and I94 respectively leadingto the valve bores enlarged end I portions I11 and I18 respectively. Thebranch passages I99 and I94 are provided intermediate their ends withone-way check valves I95 and I 96 respectively, each of which is adaptedto open to permit the flow of fluid into its corresponding end of thevalve bore whenever the pressure in said branch passages I93 and I94exceeds the opposing pressure in the corresponding end of said valvebore but which prevent the flow of fluid in the opposite direction. Thepressure existing in the discharge passage I92 and its branches I93 andI94 is regulated and held substantially constant by a pressure reliefvalve I91 connected with the passage I92 as by a passage the valvepiston I16 in its extreme position toward the right under influence ofoperating pressure in the conduit 43 and exhaust pressure (always lowand usually negligible) in the conduit 42. In this position of the valvepiston I10 the port I66 is connected with the port I64 and differentialthree heads "I, I12 and I13 respectively and 75 high presure fluidissupplied to the pair of vane slot ports 41, as in the embodiment ofFig. 8. The

, check valves I81 and I96 are closed and there is no flow of fluidthrough the valve bores enlarged end portion I18 which merely containsfluid under the same pressure as that in the conduit 43.

Both pairs of the vane slot ports 48 and 49 are continuously connectedwith the differential high pressure fluid supply, as in the embodimentof Fig. 8.

In and near the valve pistons extreme position toward the right its endportion I14 adjacent the head In closes the dash-pot recess I15 in thead- 1 jacent end cover I16, thus cutting off communication between thevalve bores enlarged end portion I11 and the conduit 42 through thepassage I8I; but it will be observed that the pressure of the fluid inthe conduit 42 is at all times active on the adjacent end of the valvepistons reduced portion I14 and will thus immediately shift the valvepiston toward the left if operating pressure fluid is admitted" to theconduit 42 and the conduit 43 is connected with the exhaust.

Further features of the arrangement and its operation will be bestunderstood by assuming that the direction of fluid flow in the conduits42 and 43 has just been reversed, that operating pressure fluid has justbeen admitted to the conduit 43 and that the valve piston I has justmoved to its extreme position toward the right in which it is shown. Ifthe rotor over-runs under high inertia load or for any other cause andcontinues to rotate in a clockwise direction (in which direction it hasbeen rotating prior to revaneslot ports 46; as the speed of the rotorde- -creases it becomes increasingly necessary that the correspondinglydecreasing centrifugal force be supplemented with an auxiliary force inorder to provide during this part of their rotary travel thetrack-following action of the vanes that is necessary for quiet andsatisfactory operasure greater than that of the fluid in the conduit.tion. This auxiliary force is supplied by fluid from the auxiliary pumpI90 which has a pres- 42 and which passes through the check valve I95,

into the valve bores enlarged end portion I11,

; through the port I65 and into the pair of vane slot ports 46 where itacts to move the vanes I1 1 radially outward and hold them in contactwith the vane track. Quiet and satisfactory operation is thus obtained.The spring of the check valve 3 I84 is preferably made such that thischeck valve will not open at the pressure required to move the vanes I1into contact with the vane track; in other words, the pressure requiredto open the check valve I84 is preferably slightly higher than thepressure maintained by the relief valve I91 so that no fluid from theauxiliary pump I90 passes through said check valve I84. The abovedescribed action continues so long as therotor continues to over-run.

When the rotor ceases to over-run and begins to rotate in acounterclockwise direction under influence of operating pressure fluidin the ports 31, the vanes I1 will -move inward during the time that theinner ends I of their corresponding vane slots I6 are connected with thepair of vane slot ports 46, and hence said vanes will discharge fluidinto said vane slot ports 46. This discharged fluid passes into thevalve bores enlarged end portion I11 where it build up a pressure thatfirst acts to close the check valve I and then to open the check valveI84 to permit fluid to be exhausted into the conduit 42. Fluiddischarged by the inner ends of the vanes is thus discharged against apressure determined by the check valve I84 but this need be only arelatively small amount of pressure that slightly exceeds the pressuremaintained by the relief valve I91; for example, the relief valve I91may be set to maintain a pressure of 20-25 lbs. per sq. in. and thecheck valve I84 may be made to open at 30-40 lbs. per sq. in. Thesesmall pressures cause no material wear or friction and do not greatlyaffect efficiency.

The valve piston I10 will be instantly moved to its extreme positiontoward the left if the flow of fluid in the conduits 42 and 43 isreversed and operating pressure fluid is admitted to the conduit 42. Theabove described connections will then be reversed. Differential highpressure fluid will be supplied to the pair of vane slot ports 46 andfluid will be admitted to and discharged from the pair of vane slotports 41 in the same manner as above described and as will be understoodfrom the foregoing explanation.

The arrangement of Fig. 9 thus provides proper vane action of all thevanes at all times and under all operating conditions and smooth, quietand eflicient operation is obtained. It will be noted, in thisconnection, that differential high pressure fluid is momentarilyadmitted to all of the vane slot ports 46, 41, 48 and 49 as the valvepiston I10 travels near and through its middle position so that quietoperation is assured during even this very small time interval.

The modification illustrated in Fig. 10, in one aspect, may be said toprovide substantially the same type of operation provided by thearrangement of Fig. 9 but does' not require the use of an auxiliarypump. As in the embodiments of Figs. 1-8 and Fig. 9, differential highpressure fluid is continuously supplied to the two pairs of vane slotports 48 and 49, for example, in the same manner as explained inconnection with Figs. 1-8. The arrangement of Fig. 10 includes a valvepiston 200 slidably fitted in a valve bore 202 for controlling the flowof fluid to and from the pair of vane slot. ports 46 and a similarseparate but oppositely positioned valve piston 20I shown as slidablyfitted in a separate valve bore 203 for controlling the flow of fluid toand from the pair of vane slots 41. The arrangement will be furtherunderstood from the following description of its operation.

v Fig. 10 shows the conduit 43, and hence a pair of ports 31, connectedwith the source of operating pressure fluid. The enlarged end portion204 of the valve bore 203 is fllled with fluid under the same pressureas that in the conduit 43, this fluid entering through the passage 205and one-way check valve 206 which opens to permit fluid from saidconduit 43 to enter said end portion 204 but closes to prevent flow offluid in the opposite direction. The force exerted by the operatingpressure fluid against the adjacent end of the valve piston 20I movessaid valve piston. to its extreme position towardthe right as determinedby a. suitable stop'201, this movement being opposed only by therelatively light spring 208 in the valve bores end209 which is at alltimes connected with the atmosphere or the reservoir as by a passage 2I0here shown as connecting with the exhaust conduit 38. In this extremeposition of, the valve piston 20I, the reduced portion thereofintermediate its heads 2 and 2l2 connects the ports M3 and 214 in thevalve bore 203. The port 2l3 is connected with the pair of. vane slotports 41 and the port 2 is at all times connected with the source of thedifferential high pressure fluid,

as by the conduit 45, so that differential high pressure fluid is thussupplied to said vane slotv ports 41. The valve piston 20! is instantlymoved to its extreme position toward the right upon admission ofoperating pressure fluid to the conduit 43, so that differential highpressure fluid is simultaneously supplied to the vane slot ports 41 atthe time that operating pressure fluid is admitted to the ports 31. Thespring-loaded one-way check valve 215, in the passage 2 l6 that alsoconnects the valve bores enlarged end portion 204 with the conduit 43,remains closed and performs no function when the conduit 43 is connectedwith the source of operating pressure fluid.

. The valve piston 230 is movable entirely independently of the valvepiston 2M and, as already stated, said valve piston 20!! controls theflow of fluid to and from the pair of vane slot ports 46 which areappropriately connected with the annular port 232 in the valve bore 202.Upon reversal of flow in the circuit so that the conduit 42 is connectedwith the exhaust conduit 33, pressure of the fluid in said conduit 42will, of course, immediately drop to a very low amount, substantiallyzero in most instances, and the pressure of the fluid in the valve boresenlarged end portion 220 will likewise drop but will never drop as lowas the pressure in the conduit 42 when said conduit 42 is connected withthe exhaust as will be presently explained. It will be observed thatfluid is unable to escape from the valve bores enlarged end portion 220through the one-way check valve 22! in the passage 222 that leads to theconduit 42 and can escape to said conduit 42 only when it reaches apressure sufiicient to open the one-way spring-loaded check valve 223 inthe passage 224. With the valve piston in a position toward the right,the port 232, and hence the pair of vane slot ports :6, are connectedwith the enlarged end portion 20. As the pressure drops in the valvebores enlarged end portion 220, the valve piston 20!! will beimmediately and correspondingly moved toward the right under influenceof the spring 225 in the end 226 of the valve bore, said end 226 beingconnected with a passage 221, shown as broken off, which may lead to theatmosphere or to a reservoir, not shown, or may connect with the exhaustconduit 38. As the valve piston 200 moves toward the right, its reducedportion 228 intermediate its heads 229 and 230 progressively connectswith the valve bores annular port 23l which is continuously connectedwith the source of differential high pressure fluid, as by a passage 45'leading from the port 2 of the valve bore 203. The valve pistons reducedportion 228 is provided with a radial hole 233 that connects with anaxial hole 234 extending through the end of the valve piston in thevalve bores enlarged end portion 220; the radial hole 233 and axial hole234 are indicated by dotted lines on the valve piston 201i and thecorresponding passages of the valve piston 20I are shown in thesectional view thereof in which they are designated by the samenumerals. A groove or slot 235 on the end of each valve piston assurescommunication at all times between the axial hole 234 and the enlargedend portion of the corresponding valve bore. fluid from the port 23| maypass into the valve bores enlarged end portion 220 to increase thepressure of the fluid therein and in the ports and passages connectedtherewith. Increase in pressure of the fluid in the valve bores enlargedend portion 220 acts to move the valve piston 200 against the spring 225and toward the left, however, and this movement tends to decrease theextent of connection between the port 23l and the valve pistons reducedportion 228, thus increasing the resistance to flow and reducing theamount of differential high pressure admitted to the end portion 220 andhence the pressure of the fluid therein. The valve piston 200 thus movesto admit suificient differential high pressure fluid to the valve boresenlarged end portion 220 to maintain therein and in the 'connected vaneslot ports 46 a pressure determined by the spring 225; the spring 225 ismade such that the pressure thus maintained is sufficient to providesatisfactory action of the vanes during over-run of the rotor atreversal while said vanes are moving in connectionwith the vane slotports 46, the pressure thus maintained being less than the pressurerequired to open the one-way spring-loaded check valve 223.

Admission of differential high pressure fluid to the enlarged endportion 220 of the valve bore, as just described, takes place onlyduring -over-run of the rotor at reversal. When the rotor ceases toover-run, or if no over-run occurs, and when the rotor begins to rotatein a counter-clockwise direction (under influence of operating pressurefluid in the ports 31) the inner ends of the vanes l1 will begin todischarge into the vane slot ports 46 as explained in connection withthe embodiments of Figs. 1-8 and Fig. 9. Fluid thus discharged canescape from the valve bores enlarged end portion 220 only through thespring-loaded check valve 223 and hence pressure is immediately built upin said enlarged end portion 220; this pressure acts first to move thevalve piston 200 toward the left until its head 230 completely coversthe port 23!, thus cutting off all admission of differential highpressure fluid to the enlarged end portion 220. The pressure built up bythe discharging inner ends of the vanes l1 then opens the check valve223, and the arrangement is such that said check valve 223 does not openuntil the valve piston 200 has moved a distance toward the leftsuflicient for its head 230 to cover the port 23!; upon opening of thecheck valve 223, fluid exhausted by the inner ends of the vanes l1passes through the passage 224,

and into the conduit 42. The pressure required to open the check valve223 need not be high and may, in fact, be only a small amount above thepressure maintained by admission of difierential high pressure fluid tothe enlarged end portion 220 during over-run, as will be understood fromthe example given in connection with the embodiment of Fig. 9. In thismanner, quiet, satisfactory and eflicient operation is obtained at alltimes, regardless of over-run of the left and will function in the samemanner In this manner diiferential high pressure 7 as already explainedin connection with the 1 like. lect such internal leakage fluid at somepoint valve piston 200 when the conduit 43 is con- A certain amount ofinternal leakage of fluid into the cavity of the casing I and adjacentthe shaft 20 will occur in devices of this character,

particularly when operated at relatively high pressures such as 1000lbs. per sq. in. and the In the past it has been customary to colbore ata point to connect with the annular groove I 2I on the outercircumference of the spacer member II5. Each passage I22 is providedintermediate its ends with a one-way check valve I23 which closes toprevent the passage of fluid from the corresponding fluid channel 40 or4I into the shaft bore but opens to permit the passage of fluid in theopposite direction in the casing and return it to the reservoir';through a separate pipe or passage; this arrangement requires extrapiping, etc. which is often inconvenient to install and adds to thetotal cost of installation of the motor. The

reversible vane type motor of the present invention provides novel,simple and inexpensive means. for returning such leakage fluid to thereservoir and one in which no extra piping or the like is required, aswill now be described.

Referring to Fig. 1, fluid leaking radially outward from the highpressure fluid areas and past the vane track ring 25 is collected in theannular passages formed by the chamfered outer edges of the cheek plates34 and 35, as indicated at I I0 and III in Fig. 1. The chamfered passageIII] .of the end head cheek plate 35 is connected with the chamferedpassage III of the casing cheek plate 34 by a groove extending axiallythrough said cheek plates and across the outer circumference of the vanetrack ring 25, this groove being indicated generally by the numeral H2.The outer face of the casing cheek plate 34 is also provided with aradial groove II3 extending from its chamfered edge III to the hole atits center, as shown in Fig. 1; the groove H3 is positioned intermediatethe ports 36 and 31 and preferably on the vertical centerline asillustrated. All fluid leaking radially outward may thus pass to thehole at the center of the cheek plate 34 and into the space suroundingthe shaft 20. Fluid leaking radially inward toward the shaft 20 collectsin the holes for said shaft 20 in the cheek plates 34 and 35, the fluidbeing free to pass axially along the shaft 20 in the spaces between theshaft splines 2I and the rotor splines I8 and may thus pass from thehole at the center of the end head cheek plate 35 to the hole at thecenter of the casing cheek plate 34. All leakage fluid thus passes tothespace between the shaft 20 and the hole for said shaft at the center ofthe casing cheek plate 34 and then through the clearance for said shaftand'through the bearing member 24.

As shown in Fig. 2, the space surrounding the shaft 20 intermediate thebearing members 23 and 24 is filled by an annular spacer member I I5,shaft packing I I6 and a gland Ill. The spacer member II5'is providedwith an annular recess I I8 on its end adjacent the bearing 24 and thisrecess II8 connects with the relatively large clearance space I I9between the inner circumference of the spacer member H5 and the shaft20. Leakage fluid is free to pass axially into the clearance space II9but is prevented from further axial travel by the shaft packing H6. Thespacer member H5 is also provided with radial holes I20 which connectthe clearance space I I9 with an annular groove or channel I2I on theouter circumference of said spacer member II5 as shown in Figs. 2 and 4.

The fluid channels 40 and II are each connected with the shaft bore inthe casing III by a whenever the pressure of the fluid in said shaftbore slightly exceeds the pressure of the fluid in the correspondingfluid channel 40 or 4|. With this arrangement, leakage fluid buildsuponly enough pressure to open the check valve I23 in the passage I22leading to whichever of the fluid channels 40 or M is at the time thedischarge or exhaust channel and connected with the exhaust conduit 38.This novel and simple arrangement thus provides for the return ofleakage fluid to the reservoir without extra pipes and is veryinexpensive; in practice it has proved entirely satisfactory.

While described and explained in connection with its use as a reversiblevane type fluid motor,

. the fluid pressure device of the present invention will also functionas a reversible pump if the shaft 20 is connected with driving meanscapable of operation in either direction of rotation. The term fluidpressure device as used in the appended claims is accordingly intendedto include both reversible pumps and reversible fluid motors. When usedas a pump, however, differential high pressure fluid cannot be providedby positioning a differential pressure or resistance valve in the supplyline and such differential high' pressure fluid must then be provided byother means such, for example, as the other means shown and fullyexplained in co-pending application Serial Number 198,449 to whichreference has already been made.

It is to be understood that the foregoing are merely exemplifyingdisclosures and that changes, some of which have been indicated, may

be made in the apparatus without departing from the invention which isdefined in the appended claims.

I claim:

1. In a reversible rotary vane type fluid motor I having a rotorprovided with a plurality of vanes movable inwardly and outwardlythereof in a substantially radial direction, a casing therefor includinga track for guiding the vanes in their in and out movement and providedwith two diametrically opposed working chambers, each working chamberhaving on opposite circumferential sides thereof two fluid areas eitherof which may be the high pressure area and the other of which will thenbethe low pressure area,

each working chamber extending in a circumferential direction a distancesubstantially equal to the distance between the outer ends of a pair ofadjacent vanes when in contact with the portion of the track-in saidchamber and each of said chambers functioning as the working chamher forwhichever of the areas on its opposite passage I22 (Fig. 4) which enterssaid shaft high pressure areas and means for supplying to the inner endsof those vanes during only but throughout the entire time that the outerends thereof are passing through said high pressure areas and saidworking chambers fluid having a pressure greater than but related to thepressure of said working pressure fluid.

2. In a reversible rotary vane type fluid mtor, a casing enclosing atrack for guiding the vanes in their inward and outward movement andhaving interchangeable fluid inlet and outlet areas, a conduit forsupplying working pressure fluid to said motor, a separate conduit forsupplying to said motor fluid having a pressure higher than that of saidworking pressure fluid, means for connecting either of said areas. withsaid working pressure fluid conduit to make it the inlet area and theother of said areas with the exhaust and means for connecting the innerends of the vanes with the higher pressure conduit during the time thatthe outer ends of said vanes are passing through the inlet area, withthe inner ends of the other vanes connected with the exhaust during thetime that the outer ends thereof are passing through the outlet area.

3. In a reversible rotary vane type fluid motor, a casing including atrack for guiding the vanes in their inward and outward movement andprovided with interchangeable fluid inlet and outlet areas,interchangeable admission and discharge ports arranged to connectsuccessively with the inner ends of the vanes, means for supplying twofluid pressures one a working and the other a higher pressure, fluidflow control. means for directly connecting either of said areas withthe working fluid pressure to make it the inlet area and the other ofsaid areas with the exhaust, and means cooperating with said ports forconnecting the inner ends of the vanes with the higher pressure duringthe time that the outer ends of said vanes are passing through the inletarea, with the inner ends of the vanes connected with the exhaust duringthe time that the outer ends thereof are passing through the outletarea.

4. In a reversible rotary vane type fluid pressure device having a rotorprovided with a plurality of vanes movable inwardly and outwardlythereof, a casing therefore including a'track for guiding the vanes intheir in and out movement and provided with interchangeable fluid inletand outlet areas either of which may be the inlet area and the other ofwhich will then be the outlet area together with means for effectinginterchange, said areas being positioned adjacent the rotor whereby theouter ends of the vanes are subjected to the respective pressures of thefluid therein as they pass therethrough, interchangeable admission anddischarge ports arranged to connect successively with the inner ends ofthe vanes as the rotor revolves, and valve means cooperating with saidports for connecting the inner ends of said vanes with the exhaustduring the time that the outer ends thereof are passing throughwhichever of said areas is at the time the outlet area and forsimultaneously supplying to the inner ends of the vanes during the timethat the outer ends thereof are passing through the other of said areaswhich is then the inlet area fluid under pressure higher than thepressure of the fluid acting on the outer ends of said vanes in saidlast named area.

5. In a reversible rotary van type fluid pressure device having aplurality of fluid sections, each fluid section comprising a workingchamber having on the opposite circumferential ends thereof two fluidareas either of which may be the high pressure area and the other ofwhich will then be the low pressure area, one circumferential end ofeach fluid section being separated from the contiguous fluid section bya sealing chamber, a rotor having a plurality of vanes movable inwardlyand outwardly thereof in a substantially radial direction, the outerends of said vanes being subjected. to the pressure of the fluid in saidchambers and said fluid areas while passing therethrough, a vane tracksurrounding said rotor and said vanes and adapted to contact the outerends of said vanes to guide and control said vanes in their in and outmovement, a separate vane slot port for each of said chambers arrangedto connect with the inner ends of the vanes while the outer ends thereofare passing through the corresponding chamber, means active to supply tothe inner ends of those vanes whose outer ends are passing throughwhichever fluid area of each fluid section is at the time its highpressure area differential high pressure fluid having a pressuregreater'than but correlated with the pressure admitted to that fluidarea and for simultaneously connecting with the exhaust the inner endsof those vanes whose outer ends are passing through the other area ofeach fluid section which is then its low pressure area, and means forcontinuously supplying said differential high pressure fluid to each ofsaid vane ports.

6. In a reversible rotary vane type fluid pressure device having a rotorprovided with a plurality of vanes movable inwardly and outwardlythereof, a casing therefor including a vane track for guiding the vanesin their in and out movement and provided adjacent the rotor with aworking chamber having on the circumferential sides thereof two fluidareas either of which may be the high pressure area and the other ofwhich willthenbe the low pressure area, a sealingchamber separating onecircumferential side of each fluid area from the contiguouscircumferential side of the adjacent fluid area, the outer ends of saidvanes being subjected to the respective pressures in said working andsealing chambers and in said fluid areas while passing therethrough, andvalve connecting and disconnecting means active to supply to the innerends of those vanes whose outer ends are passing through said workingchambers, said sealing chambers and whichever fluid area is at the timethe high pressure area fluid having a pressure greater than butcorrelated with the pressure of the fluid in said high pressure fluidarea and for simultaneously connecting with the exhaust the inner endsof those vanes whose outer ends are passing through said other fluidarea which is then the low pressure area, said valve means including atleast one element shiftable from. one position to another and havingporting means controlling solely the flow of fluid to and from the irmerends of said vanes;

7. In a reversible rotary vane type fluid pressure device having a rotorincluding a plurality of vanes movable inwardly and outwardly thereof ina substantially radial direction, a casing therefor including a trackfor guiding the vanes in their in and out movement and provided with twodiametrically opposed working chambers, each working chamber having onopposite circumferential sides thereof two fluidareas either of whichareas may be the high pressure area and the other of which will then bethe low pressure area, each of said chambers extending in acircumferential direction for an arcuate distance of said vanes aresubjected to the respective pressures therein as they pass therethrough,said and areas being positioned adjacent the rotor whereby the radiallyouter ends of said vanes are subjected to the respective pressurestherein as they pass therethrough, means for continuously supplying tothe inner ends of the vanes throughout the time that the outer endsthereof are pass- 7 ing through said working chambers fluid having apressure greater than but correlated with the pressure of the fluid inwhichever of said areas are at the time the high pressure areas, andmeans-active to supply to the inner-ends of those vanes whose outer endsare passing through the two areas that at the time are high pressureareas the fluid having said pressure greater than but correlated withthe pressure of the fluid in said high pressure areas and forsimultaneously connecting with the exhaust the inner ends of those vaneswhose outer ends are passing through the two areas that at the time arethe low pressure areas.

8. In a reversible rotary vane type fluid pressure device having a rotorprovided with a plurality of vanes movable inwardly and outwardlythereof, a casing therefor including a track for guiding the vanes-intheir in and out movement and provided with interchangeable fluid inletand outlet areas either of which may be the inlet area and the other ofwhich will then be the outlet area, said areas being positioned adjacentthe rotor whereby the outer ends of the vanes are subjected to therespective pressures of the fluid therein as they pass therethrough, andvalve means including at least one element movable responsive todifference in pressures existing in said areas for connecting the innerends of said vanes with the exhaust during the time that the outer endsthereof are passing through whichever of said areas is at the time theoutlet area and for simultaneously supplying to the inner ends of thevanes during the time that the outer ends thereof arev passing throughthe other of said areas which is then the inlet area fluid underpressure higher than but related to the pressure of the fluid acting onthe outer ends of said vanes in said last named area.

9. In a reversible rotary vane type fluid motor, a casing including atrack for guiding the' vanes in their inward and outward movement andprovided with interchangeable fluid inlet and outlet areas, means forsupplying two fluid pressures one a working and the other a higherpressure, means for connecting either of said areas with working fluidpressure to make it the inlet area and the other of said areas with theexhaust and means including an element movable responsive to differencein pressures existing in said areas for connecting the inner ends of thevanes with the higher pressure during the time that the outer ends :ofsaid vanes are passing through the inlet area, with the inner ends ofthe vanes connected with the exhaust during the time that the outer endsthereof are passing through the outlet area.

10. In a reversible rotary vane type fluid motor having a rotor providedwith a plurality of vanes movable inwardly and outwardly thereof in asubstantially radial direction, a casing therefor including a vane trackfor guiding the vanes in their in and out movement and having two fluidareas adjacent the rotor whereby the outer ends make either one of themthe high pressure area and the other of them the low pressure area, the

, direction of rotation of said rotor being reversed those vanes whoseouter ends are passing through the high pressure area fluid underpressure greater than but correlated with the pressure of the fluid insaid high pressure area, and, during over-run of said rotor, forsupplying to the inner ends of those vanes whose outer ends are passingthrough the low pressure area fluid having a pressure less than thepressure of the fluid in the high pressure area but greater than thepressure in the low pressure area to urge said vanes into contact withsaid vane track independent of the action of centrifugalforce.

11. In a reversible rotary vane type fluid motor having a rotor providedwith a plurality of vanes movable inwardly and outwardly thereof in asubstantially radial direction, a casing therefor including a vane trackfor guiding the vanes in their in and out movement and having two fluidareas adjacent the rotor whereby the outer ends of said vanes aresubjected to the respective pressures therein as they pass therethrough,said fluid areas being interchangeably connectable to make either one ofthem the high pressure area and the other of them the low pressure area,the direction of rotation of said rotor being reversed by saidinterchange and said rotor tending upon said interchange to momentarilyover-run and to continue to rotate in the direction of its rotationprior to said interchange, means automatically active upon saidinterchange to supply to the inner ends of those vanes whose outer endsare passing through the high pressure area, fluid under pressure greaterthan but I correlated with the pressure of the fluid in said highpressure area, and, during over-run of said rotor, for supplying to theinner ends of those vanes whose 12. In a reversible rotary vane typefluid motor having a rotor provided with a plurality of vanes movableinwardly and outwardly thereof in a substantially radial direction, acasing therefor including a vane track for guiding the vanes in their inand out movement and having two fluid areas adjacent the rotor wherebythe outer ends of said vanes are subjected to the respective pressurestherein as they pass therethrough, said fluid areas having connectionsinterchangeable tomake either one of them the high pressure area and theother of them the low pressure area, the direction of rotation of saidrotor being reversed upon interchange of high pressure a from one ofsaid areas to the other and corresponding interchange of low pressureareas but said rotor tending upon such interchange to momentarilyover-run and to continue to rotate in the direction of its rotationprior to said interchange, means active upon said interchange to supplyto the irmer ends of those vanes whose outer ends are passing throughthe high pressure area differential high pressure fluid under pressuregreater than but related to the pressure of the fluid in said highpressure area and means for supplying during over-run of said rotor anauxiliary force active to move said vanes into contact with the vanetrack as the outer ends thereof pass through said low pressure area,saidauxiliary force being of a magnitude sufficient to move said vanes intocontact withsaid vane track but insuflicient to produce heavy rubbingaction of said vanes against said vane track.

13. In a reversible rotary vane type fluid motor having a rotor providedwith a plurality of vanes movable inwardly and outwardly thereof, acasing therefor including a track for guiding the vanes in their in andout movement and provided with interchangeable fluid inlet and outletareas either of which may be the inlet area and the other of which willthen be the outlet area, said areas being positioned adjacent the rotorwhereby the outer ends of the vanes are subjected to the respectivepressures of the fluid therein as they pass therethrough, a vane slotport adapted to connect with the inner ends of those vanes whose outerends are passing through one of said areas, a separate vane slot portadapted to connect with the inner ends of those vanes whose outer endsare passing through the other of said areas, a valve bore havingseparate ports therein separately connected with said vane slot ports, afluid admission port in said valve bore connected with a supply of fluidhaving a pressure higher than but related to the pressure of the fluidin whichever of said areas is at the time the inlet area, a fluidconnection between one end of said valve bore and one of said areas andanother fluid connection between the other end of said valve bore andthe other of said areas, and a valve piston in said valve bore havingits ends continuously exposed to fluid admitted to the ends of saidvalve bore from said areas, whereby said valve piston is instantly movedto and maintained in one of its two extreme positions of movement insaid valve bore responsive to diflerence in pressures of fluid therein,said valve piston establishing when in said extreme positions fluidconnection between said fluid. admission port and the port in said valvebore that is connected with the inner ends of those vanes whose outerends are passing through whichever of said areas is at the time theinlet area and also establishing direct and unobstructed fluidconnection between the passage in the end of said valve bore leading tosaid other area and the port in said valve bore connected with the innerends of those vanes whose outer ends are passing through the other ofsaid areas which is the outlet area.

14. In a reversible rotary vane type fluid motor having a rotor providedwith a plurality of vanes movable inwardly and outwardly thereof, acasing therefor including a vane track for guiding the vanes in their inand out movement and provided adjacent the rotor with a working chamberhaving on the circumferential sides thereof two fluid areas either ofwhich may be the inlet area and the other of which will then be theoutlet area, said working chamber extending in a circumferentialdirection a distance substantially equal to the distance between theouter ends of a pair of adjacent vanes when in contact with the portionof the vane track in said chamber, means for connecting either of saidareas with working pressure fluid to thereby make it the inlet area andmeans forsupplying to the inner ends of at least certain of the vanesfluid under pressure slightly higher than the pressure of said workingpressure fluid, said means including a vane slot port adapted to connectwith the inner ends of those vanes whose outer ends are passing throughone of said areas, a separate vane slot port adapted to connect with theinner ends of those vanes whose outer ends are passing through the otherof said areas, a valve bore having separate ports therein separatelyconnected with said vane slot ports, a fluid admission port in saidvalve bore connected with a supply of fluid having a pressure higherthan but related to the pressure of the fluid in whichever of said areasis at the time the inlet area, and piston valve means in said valve boreactive to connect said fluid admission port with the port in said valvebore which is connected with that vane slot port which is in connectionwith the inner ends of those vanes whose outer ends are passing throughwhichever of said areas is at the time the inlet area.

15. In a reversible vane type fluid motor having a rotor provided with aplurality of vanes movable inwardly and outwardly thereof,

' bore but preventing the passage of fluid in the a casing thereforincludin a track for guiding the vanes intheir in and out movement andprovided with interchangeable high and low pressure fluid areas adjacentthe rotor whereby the outer ends of said vanes are subjected to therespective pressures of the fluid therein as they pass therethrough, avane slot port adapted to connect with the inner ends of those vaneswhose outer ends are passing through one of said areas, a separate vaneslot port adapted to connect with the inner ends of those vanes whoseouter ends are passing through the other of said areas, a valve borehaving separate ports therein separately connected with a supply offluid having a pressure greater than but related to the pressure of thefluid admitted to whichever of said areas is at the time the highpressure area, a valve piston in said valve bore having its endscontinuously exposed to the respective pressures in said areas wherebysaid valve piston is instantly moved to andmaintained in one of its twoextreme positions of movement in said valve bore responsive todifference of pressure in said areas, said valve piston establishingwhen in said extreme positions fluid connection between said fluidadmission port and the vane slot port that is connected with the innerends of those vanes whose outer ends are passing through whichever ofthe areas is at the time the high pressure area, and also establishingfluid'connection between said other vane slot port and the end of thevalve bore adjacent the end of said valve piston exposed to pressureoffluid in the low pressure area, an aurdliary pump, means for maintainingthe fluid discharged by said aum'liary pump at a substantially constantpressure, a fluid connectionbetween said last named end of said valvebore and the discharge of said auxiliary pump, a check valve in saidlast named fluid connection adapted to open to admit pressure fluid fromsaid pump to said end of said valve opposite direction, and a fluidconnection between said last named end'of said valve bore and said lowpressure area and having a check the pressure of the fluid discharged bysaid auxiliary pump.

16. In a'reversible rotary vane type fluid motor having a rotor providedwith a plurality of vanes movable inwardly and outwardly thereof in asubstantially radial direction, a casing therefor including a vane trackfor guiding the vanes in their in and out movement and having two fluidareas adjacent the rotor whereby the outer ends of said vanes aresubjected to the respective pressures therein as they pass therethrough,said fluid areas being interchangeably connectable to make either one ofthem the high pressure area and the other of them the low pressure area,the

continue to rotate in the direction of its rotation prior to saidinterchange, means active upon said interchange to supply to the innerends .of those vanes whose outer ends are passing through the' 1highpressure area fluid under pressure greater than but correlated with thepressure of the fluid in said high pressure area, and, during over- ;runof said rotor, for supplying to the inner ends of those vanes whoseouter ends are passing through the low pressure area fluid having apressure less than the pressure of the fluid in the high pressure areabut greater than the pressure in the low pressure area to urge saidvanes into contact with said vane track independent of the action ofcentrifugal force, said last fnarned means including an auxiliary pumpfor supplying pressure fluid to the inner ends of those vanes whoseouter ends are passing through said low pressure area during over-run tourge said vanes into contact with the vane track.

1'7. In a reversible rotary vane type fluid motor having a rotorprovided with a plurality of vanes movable inwardly and outwardlythereof in a substantially radial direction, a casing therefor includinga, vane track for guiding the vanes in their in and out movement andhaving two fluid areas adjacent the rotor whereby the outer endscontinue to rotate in the direction of its rotation prior to saidinterchange, means active upon said interchange to supply to the innerends of those vanes whose outer ends are passing through the highpressure area fluid under pressure greater than but correlated with thepressure of the fluid in said high pressure area, and, during over-runof said rotor, for supplying to the inner ends of those vanes whoseouter ends are passing through the low pressure area fluid having apressure less than the pressure of the fluid in the high pressure areabut greater than the pressure in the low pressure area to urge saidvanes into contact with said vane track independent of the action ofcentrifugal force, said last named means including a vane slot portadapted to connect with the inner ends of those van:

whose outer ends are passing through one 'of said fluid areas, aseparate vane slot port-adapted to connect with the inner ends of thosevanes whose outer ends are passing through the other fluid area andseparate piston means for controlling the flow of fluid to and from eachof said vane slot ports.

18. In a reversible rotary vane type "fluid motor having a rotorprovided with a plurality of vanes movable inwardly and outwardlythereof, a vane track for guiding the vanes in their in and out movementand provided adjacent the rotor with a working chamber having on theopposite circumferential sides thereof two fluid areas either of whichmay be the inlet area and the other of which will then be the outletarea, a separate port positioned to connect with the inner ends of thevanes during only the time that the outer ends thereof are passingthrough said chamber, means for connecting either of said areas with theworking pressure fluid supply to thereby make it the inlet area andmeans for continuously supplying to said port fluid having a pressuregreater than but related to the pressure of the working pressure fluid.

19. In a rotary vane type fluid pressure device, a rotor having aplurality of vanes movable inwardly and outwardly thereof, a track forguiding the vanes in their in and out movement and provided adjacent therotor with a working chamber having an inlet area and an outlet area onthe opposite circumferential sides thereof, one of said areas containingworking pressure fluid, a port arranged to connect with the of arepassing through the inlet area fluid having a pressure greater than thepressure of the fluid in said inlet area.

20. In a reversible rotary vane type fluid pressure device, a rotorhaving a plurality of vanes movable inwardly and outwardly thereof, avane track for guiding said vanes in their in and out movement, a firstfluid area and a second fluid area either of which may be the inlet areaand the other of which will then be the outlet area, said areas beingpositioned adjacent said track and said rotor whereby the outer ends ofthe vanes are subjected to the respective pressures continuouslyconnected with a sourc of pressure fluid having a pressure greaterthanthat of the fluid in whichever of the areas is the inlet area,

and a valve element in said bore movable responsive to difference ofpressures in said areas and active to connect said fluid admission portwith the vane slot port for whichever of said areas is at the time theinlet area and to connect the vane slot port for the other of said areaswith the discharge.

21. In a reversible rotary vane type fluid motor, a rotor having aplurality of vanes movable inwardly and outwardly thereof, a vane trackfor guiding the vanes in their in and out movement and provided withcircumferentially sepa-

